convert rxjava to live data in presentation layer

app/build.gradle

@@ -76,6 +76,8 @@ dependencies {
     // acc
     implementation "android.arch.lifecycle:extensions:1.1.0"
     implementation "android.arch.lifecycle:viewmodel:1.1.0"
+    implementation "android.arch.lifecycle:livedata:1.1.0"
+    implementation "android.arch.lifecycle:reactivestreams:1.1.0"
     kapt "android.arch.lifecycle:compiler:1.1.0"
 
     // rx

app/src/main/java/com/enixma/sample/charity/domain/UseCase.kt

@@ -1,10 +1,10 @@
 package com.enixma.sample.charity.domain
 
-import io.reactivex.Observable
+import io.reactivex.Flowable
 
 interface UseCase<in P : UseCase.Request, Q : UseCase.Result> {
 
-    fun execute(request: P): Observable<Q>
+    fun execute(request: P): Flowable<Q>
 
     interface Request
 

app/src/main/java/com/enixma/sample/charity/domain/createdonation/CreateDonationUseCase.kt

@@ -2,27 +2,30 @@ package com.enixma.sample.charity.domain.createdonation
 
 import com.enixma.sample.charity.data.repository.ICharityRepository
 import com.enixma.sample.charity.domain.UseCase
-import io.reactivex.Observable
+import io.reactivex.BackpressureStrategy
+import io.reactivex.Flowable
 import javax.inject.Inject
 
 class CreateDonationUseCase @Inject constructor(private val charityRepository: ICharityRepository) : UseCase<CreateDonationUseCaseRequest, CreateDonationUseCaseResult> {
 
     enum class STATUS {
+        LOADING,
         SUCCESS,
         FAIL
     }
 
-    override fun execute(request: CreateDonationUseCaseRequest): Observable<CreateDonationUseCaseResult> {
-        return charityRepository.createDonation(request.donationEntity)
-                .flatMap {
-                    val result = it.let {
-                        val status = if (it.statusCode == 201 && it.isSuccess) STATUS.SUCCESS else STATUS.FAIL
-                        CreateDonationUseCaseResult(status).apply {
-                            if (this.status == STATUS.FAIL) this.errorMessage = it.errorMessage
-                        }
-                    }
-                    Observable.just(result)
-                }
-
+    override fun execute(request: CreateDonationUseCaseRequest): Flowable<CreateDonationUseCaseResult> {
+        return Flowable.just(CreateDonationUseCaseResult(STATUS.LOADING)).concatWith(
+                charityRepository.createDonation(request.donationEntity)
+                        .toFlowable(BackpressureStrategy.LATEST)
+                        .flatMap {
+                            val result = it.let {
+                                val status = if (it.statusCode == 201 && it.isSuccess) STATUS.SUCCESS else STATUS.FAIL
+                                CreateDonationUseCaseResult(status).apply {
+                                    if (this.status == STATUS.FAIL) this.errorMessage = it.errorMessage
+                                }
+                            }
+                            Flowable.just(result)
+                        })
     }
 }

app/src/main/java/com/enixma/sample/charity/domain/getcharitylist/GetCharityListUseCase.kt

@@ -2,25 +2,29 @@ package com.enixma.sample.charity.domain.getcharitylist
 
 import com.enixma.sample.charity.data.repository.ICharityRepository
 import com.enixma.sample.charity.domain.UseCase
-import io.reactivex.Observable
+import io.reactivex.BackpressureStrategy
+import io.reactivex.Flowable
 import javax.inject.Inject
 
 class GetCharityListUseCase @Inject constructor(private val charityRepository: ICharityRepository) : UseCase<GetCharityListUseCaseRequest, GetCharityListUseCaseResult> {
 
     enum class STATUS {
+        LOADING,
         SUCCESS,
         NO_DATA_FOUND
     }
 
-    override fun execute(request: GetCharityListUseCaseRequest): Observable<GetCharityListUseCaseResult> {
-        return charityRepository.getCharityList()
-                .flatMap {
-                    val result = it.let {
-                        val status = if (it.total <= 0) STATUS.NO_DATA_FOUND else STATUS.SUCCESS
-                        val charityList = it.data
-                        GetCharityListUseCaseResult(status, charityList)
-                    }
-                    Observable.just(result)
-                }
+    override fun execute(request: GetCharityListUseCaseRequest): Flowable<GetCharityListUseCaseResult> {
+        return Flowable.just(GetCharityListUseCaseResult(STATUS.LOADING, mutableListOf())).concatWith(
+                charityRepository.getCharityList()
+                        .toFlowable(BackpressureStrategy.LATEST)
+                        .flatMap {
+                            val result = it.let {
+                                val status = if (it.total <= 0) STATUS.NO_DATA_FOUND else STATUS.SUCCESS
+                                val charityList = it.data
+                                GetCharityListUseCaseResult(status, charityList)
+                            }
+                            Flowable.just(result)
+                        })
     }
 }

app/src/main/java/com/enixma/sample/charity/domain/validatecreditcard/ValidateCreditCardUseCase.kt

@@ -2,6 +2,7 @@ package com.enixma.sample.charity.domain.validatecreditcard
 
 import co.omise.android.CardNumber
 import com.enixma.sample.charity.domain.UseCase
+import io.reactivex.Flowable
 import io.reactivex.Observable
 
 class ValidateCreditCardUseCase : UseCase<ValidateCreditCardUseCaseRequest, ValidateCreditCardUseCaseResult> {
@@ -18,7 +19,7 @@ class ValidateCreditCardUseCase : UseCase<ValidateCreditCardUseCaseRequest, Vali
         INVALID_LUHN
     }
 
-    override fun execute(request: ValidateCreditCardUseCaseRequest): Observable<ValidateCreditCardUseCaseResult> {
+    override fun execute(request: ValidateCreditCardUseCaseRequest): Flowable<ValidateCreditCardUseCaseResult> {
 
         val errorList = ArrayList<ERROR>()
         validateCard(request.cardNumber, errorList)
@@ -27,7 +28,7 @@ class ValidateCreditCardUseCase : UseCase<ValidateCreditCardUseCaseRequest, Vali
 
         return errorList.let {
             val status = if (it.isEmpty()) STATUS.VALID else STATUS.INVALID
-            Observable.just(ValidateCreditCardUseCaseResult(status).apply { this.errorList = it })
+            Flowable.just(ValidateCreditCardUseCaseResult(status).apply { this.errorList = it })
         }
     }
 

app/src/main/java/com/enixma/sample/charity/presentation/charitylist/CharityListFragment.kt

@@ -41,7 +41,7 @@ class CharityListFragment : Fragment(), CharityListContract.View {
         DaggerCharityListComponent.builder()
                 .serviceFactoryModule(ServiceFactoryModule(activity))
                 .charityDataModule(CharityDataModule(activity))
-                .charityListModule(CharityListModule(this))
+                .charityListModule(CharityListModule(this, this))
                 .build().inject(this)
     }
 
@@ -54,7 +54,6 @@ class CharityListFragment : Fragment(), CharityListContract.View {
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
 
-        lifecycle.addObserver(presenter as CharityListPresenter)
         binding.swipe.setOnRefreshListener { presenter.getCharityList() }
         binding.swipe.isRefreshing = true
         presenter.getCharityList()

app/src/main/java/com/enixma/sample/charity/presentation/charitylist/CharityListPresenter.kt

@@ -1,42 +1,48 @@
 package com.enixma.sample.charity.presentation.charitylist
 
-import android.arch.lifecycle.Lifecycle
-import android.arch.lifecycle.LifecycleObserver
-import android.arch.lifecycle.OnLifecycleEvent
+import android.arch.lifecycle.*
+import android.util.Log
+import android.widget.Toast
 import com.enixma.sample.charity.domain.getcharitylist.GetCharityListUseCase
 import com.enixma.sample.charity.domain.getcharitylist.GetCharityListUseCaseRequest
 import com.enixma.sample.charity.domain.getcharitylist.GetCharityListUseCaseResult
-import io.reactivex.disposables.Disposable
 
 class CharityListPresenter(private val view: CharityListContract.View,
-                           private val getCharityListUseCase: GetCharityListUseCase) : CharityListContract.Action, LifecycleObserver {
+                           private val lifecycleOwner: LifecycleOwner,
+                           private val getCharityListUseCase: GetCharityListUseCase) : CharityListContract.Action {
 
-    private var getCharityListDisposable: Disposable? = null
-    private var isLoading: Boolean = false
+    private var result: LiveData<GetCharityListUseCaseResult> = MutableLiveData()
+    private var resultObserver: Observer<GetCharityListUseCaseResult>
+
+    init {
+        resultObserver = Observer<GetCharityListUseCaseResult> { result ->
+            processGetCharityListResult(result)
+        }
+    }
 
     override fun getCharityList() {
 
-        if (isLoading) {
+        if (result.value?.status == GetCharityListUseCase.STATUS.LOADING) {
             return
         }
 
-        isLoading = true
-        getCharityListDisposable = getCharityListUseCase.execute(GetCharityListUseCaseRequest())
-                .doOnNext { result -> processGetCharityListResult(result) }
-                .subscribe()
+        result = LiveDataReactiveStreams.fromPublisher(getCharityListUseCase.execute(GetCharityListUseCaseRequest()))
+        result.observe(lifecycleOwner, resultObserver)
     }
 
-    private fun processGetCharityListResult(result: GetCharityListUseCaseResult) {
-        isLoading = false
-        if (result.status == GetCharityListUseCase.STATUS.SUCCESS) {
-            view.populateList(result.charityList)
-        } else {
-            view.displayNoData()
+    private fun processGetCharityListResult(result: GetCharityListUseCaseResult?) {
+        result?.let {
+            when (it.status) {
+                GetCharityListUseCase.STATUS.LOADING -> {
+                    // do nothing
+                }
+                GetCharityListUseCase.STATUS.SUCCESS -> {
+                    view.populateList(it.charityList)
+                }
+                else -> {
+                    view.displayNoData()
+                }
+            }
         }
     }
-
-    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
-    fun onPresenterDestroy() {
-        getCharityListDisposable?.dispose()
-    }
 }

app/src/main/java/com/enixma/sample/charity/presentation/charitylist/di/CharityListModule.kt

@@ -1,5 +1,6 @@
 package com.enixma.sample.charity.presentation.charitylist.di
 
+import android.arch.lifecycle.LifecycleOwner
 import com.enixma.sample.charity.domain.getcharitylist.GetCharityListUseCase
 import com.enixma.sample.charity.presentation.charitylist.CharityListContract
 import com.enixma.sample.charity.presentation.charitylist.CharityListPresenter
@@ -8,10 +9,10 @@ import dagger.Provides
 import javax.inject.Inject
 
 @Module
-class CharityListModule(private val view: CharityListContract.View) {
+class CharityListModule(private val view: CharityListContract.View, private val lifecycleOwner: LifecycleOwner) {
     @Provides
     @Inject
     fun provideCharityListPresenter(getCharityListUseCase: GetCharityListUseCase): CharityListContract.Action {
-        return CharityListPresenter(view, getCharityListUseCase)
+        return CharityListPresenter(view, lifecycleOwner, getCharityListUseCase)
     }
 }

app/src/main/java/com/enixma/sample/charity/presentation/donation/DonationContract.kt

@@ -5,7 +5,8 @@ import co.omise.android.models.Token
 interface DonationContract {
     interface View {
         fun displayError(errorMessage: String)
-
+        fun displayLoading()
+        fun dismissLoading()
         fun goToSuccessScreen()
     }
 

app/src/main/java/com/enixma/sample/charity/presentation/donation/DonationFragment.kt

@@ -13,6 +13,7 @@ import android.view.View
 import android.view.ViewGroup
 import co.omise.android.models.Token
 import com.bumptech.glide.Glide
+import com.enixma.sample.charity.BuildConfig
 import com.enixma.sample.charity.R
 import com.enixma.sample.charity.data.di.ServiceFactoryModule
 import com.enixma.sample.charity.data.di.CharityDataModule
@@ -21,6 +22,7 @@ import com.enixma.sample.charity.presentation.creditcard.AddCreditCardActivity
 import com.enixma.sample.charity.presentation.donation.di.DaggerDonationComponent
 import com.enixma.sample.charity.presentation.donation.di.DonationModule
 import com.enixma.sample.charity.presentation.success.SuccessActivity
+import org.json.JSONObject
 import javax.inject.Inject
 
 
@@ -61,7 +63,7 @@ class DonationFragment : Fragment(), DonationContract.View {
         DaggerDonationComponent.builder()
                 .serviceFactoryModule(ServiceFactoryModule(activity))
                 .charityDataModule(CharityDataModule(activity))
-                .donationModule(DonationModule(this, viewModel))
+                .donationModule(DonationModule(this, this, viewModel))
                 .build().inject(this)
     }
 
@@ -74,18 +76,31 @@ class DonationFragment : Fragment(), DonationContract.View {
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
 
-        lifecycle.addObserver(presenter as DonationPresenter)
         initProgressDialog()
         initDonationAmountSelection()
         populateImage()
         binding.editAmount.setOnClickListener {
             displayAmountSelectionDialog()
         }
         binding.buttonDonate.setOnClickListener {
-            displayConfirmDialog()
+            if(!BuildConfig.DEBUG){
+                displayConfirmDialog()
+            } else {
+                // skip add credit card
+                presenter.donate(Token(JSONObject()))
+                progressDialog.show()
+            }
         }
     }
 
+    override fun displayLoading() {
+        progressDialog.show()
+    }
+
+    override fun dismissLoading() {
+        progressDialog.dismiss()
+    }
+
     private fun initProgressDialog() {
         progressDialog = ProgressDialog(activity)
         progressDialog.setMessage(getString(R.string.alert_message_submit_donation))
@@ -141,12 +156,10 @@ class DonationFragment : Fragment(), DonationContract.View {
     }
 
     override fun goToSuccessScreen() {
-        progressDialog.dismiss()
         startActivityForResult(SuccessActivity.getIntent(activity, viewModel.name, viewModel.amount.get()), REQUEST_FINAL)
     }
 
     override fun displayError(errorMessage: String) {
-        progressDialog.dismiss()
         alertDialog = AlertDialog.Builder(activity).apply {
             var message = if (errorMessage.isNullOrBlank()) getString(R.string.alert_message_communication_error) else errorMessage
             this.setTitle(R.string.alert_title_error)